Exemplary embodiments of the invention relate to an airbag for a vehicle and a vehicle comprising at least one such airbag.
Airbags for vehicles are known in general from the prior art. Such airbags cover different areas inside or outside the vehicle and reduce the risk of an impact of vehicle occupants or other travelers against the covered areas of the vehicle. An airbag comprises at least one inflatable chamber, which in the event of a triggering is filled with a gas using a fluid-coupled gas generator. As the at least one chamber is being filled, the airbag deploys from a non-use position into a use position.
Exemplary embodiments are directed to an airbag that is improved over the prior art and an improved vehicle.
The airbag for a vehicle comprises at least one chamber that can be inflated when the airbag is triggered and at least one gas chamber fluidically connected to the at least one chamber for filling the at least one chamber with a gas. According to the invention, at least one respective inner tensioning bag is arranged at each opposite chamber end in the at least one chamber, wherein the two tensioning bags are configured in such a way that as the at least one chamber is being filled, these bags expand and tension in a synchronized manner and deploy the chamber.
Long tensioning or expansion paths in airbags with large surface areas, such as airbags or safety cloths or safety nets or protective nets serving as dividing elements or partitions in the vehicle interior, are avoided by an airbag configured in this manner. Furthermore, the entire chamber is not filled with gas. During the gas or pressure filling of the airbag, the internal tensioning bags in the chamber are inflated and thus everted or evaginated in the axial direction toward the chamber middle and thereby support the chamber in the everted and inflated state from inside. In other words, the airbag comprises an outer airbag, which forms the chamber, and a plurality of inner tensioning bags, which are also configured as airbags (also known as a tube-in-tube airbag). The inner tensioning bags can thus be tensioned like a muscle during the filling of the chamber and hence of the outer airbag, whereby the outer airbag and hence the chamber are moved, in particular deployed and tensioned.
In one possible embodiment, at least one respective inner tensioning bag is arranged at each opposite chamber end in the at least one chamber, wherein in the unfilled state of the chamber, the respective tensioning bag is invaginated in a starting position in the chamber, in particular toward a portion of the chamber containing a gas flow. Particularly in the event of triggering, the chamber can then be filled with a gas in such a way that the respective tensioning bag, which is invaginated when in the starting position, is evaginated from the starting position into a tensioning position inside the chamber after filling. As a consequence, the chamber and thus the airbag are deployed and tensioned.
According to another embodiment at least one associated tensioning element per tensioning bag is guided through a passage opening from an exterior of the chamber into an interior of the chamber and is fastened at a bag end opposite a bag opening of the invaginated tensioning bag, and wherein the chamber can be filled at the chamber ends with the gas in such a way that the respective tensioning bag, which is invaginated in the starting position, is evaginated from the respective chamber portion from the starting position into an tensioning position after filling, wherein the associated tensioning elements tension the tensioning bags through the respective passage opening in opposing tensioning directions.
By means of the airbag with interior tensioning bags capable of being evaginated and inflated, a displacement and thus a tensioning function of the tensioning element can be effected in addition to a cushioning function resulting from the inflation for reducing the risk of injury or for tensioning a dividing element or occupant protection element. A length of the displacement thus corresponds to a length of the invaginated tensioning bag in the chamber, in the starting position. The displacement of the tensioning element and thus the tensioning force can be adjusted in an expedient manner by selecting the length of the chamber and the length of the invaginated tensioning bag.
Depending on the type and size of the airbag, the tensioning bags can be configured and integrated in the chamber in such a way that, in the evaginated state and thus in the filled state of the chamber, they are disposed adjacently to one another therein. For example, an elongate, in particular tube-shaped airbag is thus filled with gas from two ends. In particular, the interior and invaginated tensioning bags are filled synchronously with the gas from opposite ends so that the tensioning bags are evaginated and deployed in such a way that their bag ends move toward one other and are adjacent to one another in the filled state of the chamber. Even a large elongate airbag can thus be filled quickly and easily.
In an alternative embodiment, the tensioning bags are configured and integrated in the chamber in such a way that, in the evaginated state and thus in the filled state of the chamber, they lie on top of one another therein. For example, a tall and less elongate airbag is thus filled with gas from two ends. In particular, the interior and invaginated tensioning bags are filled synchronously with the gas from opposite ends so that the tensioning bags are evaginated and deployed in such a way that their bag ends move toward and past one another and are arranged at chamber ends opposite each other in the filled state of the chamber. In the filled state of the chamber, the evaginated tensioning bags are thus disposed in parallel above one another. Even a large tall or wide airbag can thus be filled quickly and easily.
In particular for reducing the required gas volume, the respective tensioning bag is fastened to the chamber and fluidically connected to the chamber by a peripheral seam. The respective tensioning bag is fluidically connected to the chamber portion, which is fluidically connected to the gas generator. The tensioning element is thus guided via a passage opening into the chamber, and connected to the invaginated bag end in the interior of the chamber.
Depending upon the nature of the arrangement of the gas generator and the gas infeed, in an alternative embodiment the respective tensioning element can be arranged between the gas generator and the chamber in a fluid-tight sheath. The sheath is configured as an airbag trunk via which gas flows into the chamber when the airbag is triggered.
The tensioning element is configured as an active tensioning resulting from the deployment of the chamber in such a way that, in advantageous fashion, an additional actuator is not needed for actuating the tensioning element. In a possible embodiment, the tensioning element is configured as a tensioning cable or a tensioning strap.
A possible development includes a brake for braking a displacement of the tensioning element in opposition to the tensioning direction is arranged in the zone of the passage opening. In a particularly advantageous fashion, the brake enables the tensioning element to be held in its tensioned position after an active tensioning brought about by inflation of the chamber. An additional, ongoing generation of a tensioning force by means of the chamber is therefore not required.
The airbag can, in particular, be used as a separating device (partition) or as an occupant protection device, which is automatically triggered in the event of an accident. To this end, the gas generator is controlled by a control unit which, for example, controls other occupant protection devices in the vehicle such as airbags and/or seatbelt tensioners.
According to the invention, a vehicle comprises such an airbag. For example, such an airbag as described in the preceding is arranged as a partition in a roof frame of the vehicle. As an alternative, the airbag can be a window airbag or an occupant protection device. By means of the airbag, a displacement and thus a tensioning function of the tensioning element can be effected in addition to a cushioning function resulting from the inflation for reducing the risk of injury or for tensioning a separation element or occupant protection element. A length of the displacement thus corresponds to a length of the invaginated portion of the chamber in the starting position. The displacement of the tensioning element and thus the tensioning force can be easily adjusted by selection of the length of the chamber and of the length of the invaginated tensioning bag.
In all figures, corresponding parts are designated by the same reference signs.